Thomas Wyatt: The Heart's Forest by Susan Brigden - review

In winter 1541 Thomas Wyatt, imprisoned in the Tower on charges of high treason, was awaiting judgment. For anybody ambitious or unlucky enough to be caught up in the religion-infused politics of these years – years in which the psychodramas of an ageing, corpulent Henry VIII reached a new, fevered pitch – simply surviving was an achievement. In July the previous year, Thomas Cromwell, the man whom Wyatt served, had fallen victim to a factional coup; now he was caught up in the fall-out, accused by his enemies of plotting with the king's bugbear, the exiled papal loyalist Cardinal Reginald Pole. Like other political prisoners before him, Wyatt wrote for his life. In his defence, a brilliant piece of rhetorical plain-speaking, he made a simple request to the judges and jury: not to be swayed by the prosecution's bluster, but to consider the unvarnished evidence: "Rehearse here the law of words."

After centuries of literary-critical sneering at Wyatt's work, scholars now see him for what he was: the supreme English wordsmith of his age. Our fascination with his life continues to revolve around his association with Anne Boleyn, whose lover he may have been, and with the romantic narrator of his poems, whose anguished memory of a love now lost keeps him awake at nights: "all is turned through my gentleness / Into a strange fashion of forsaking."

Wyatt's genius was known and admired in his own time. Like Cromwell, he was an inglese italianizzato, and his bold experimenting in English with the verse-forms and sensibilities of the Italian renaissance – he wrote the first English sonnet – had a profound influence on our literary language. But his skill was to find a poetic voice that was at once distinctive and sinuous enough to reflect and adapt itself to the convulsive times in which he became intricately entangled.

Wyatt was audacious, charismatic and restless – qualities that resonate through his poems and which took him to the heart of high politics. Abroad, as "king's orator", his work blurred into something more shadowy: working against the enemies of the nascent English state, he was involved in distinctly undiplomatic attempts at extraordinary rendition and assassination. He also, crucially, had an instinct for survival – notably in 1532 when, along with others in Boleyn's circle, he was committed to the Tower for the first time, looking on at the executions from his cell window: "The bell tower showed me such sight / That in my head sticks day and night."

In order to survive and prosper, Wyatt did what all courtiers had to do. He made politic and powerful friends, trimmed his own attitudes, opinions and religious beliefs to those that prevailed – and was ready to abandon or betray all of them at the drop of a hat. Like so many, Wyatt easily shifted his support of Catherine of Aragon to Anne Boleyn, and with it his faith; he also made a tidy sum out of the dissolution of the monasteries.

Wyatt's poems strike at the heart of the courtier's – or, more broadly, politician's – dilemma: how to remain constant, or true, or to retain any sense of perspective or self, in such a situation? "Each man telleth me I change most my devise, / And on my faith I think it good reason / To change purpose after the like season." But in tackling these themes, Wyatt's poems could hardly be overtly topical: in the environment in which he moved, that would have been a sure route to the executioner's block. As he put it: "It is a small thing in altering of one syllable either with pen or word that may make in the conceiving of the truth much matter of error."

Wyatt revelled in semantic slipperiness, and any account of his life and work must involve a negotiation between some of the most brilliantly evasive poetry in the English language and often hazy, historical fact: trying to connect the one to the other is an exercise in nailing jelly to a wall. As one of the foremost authorities on Wyatt and his age, Susan Brigden is of course all too aware of this. Her monumental new book, the result of many years' work, is the richest and most exhaustive study on Wyatt to date.

Very different in tone and approach to Nicola Shulman's recent and acclaimed Graven with Diamonds, it comprises in large part a sequence of close textual readings of Wyatt's poems, teasing apart his language and syntax, and scrutinising them in the light of his career, his literary influences and the political and intellectual culture of the time. If this sounds recondite, it is – readers coming to Wyatt for the first time might be advised to read Shulman and Brigden in tandem – but to say this is by no means to underplay Brigden's achievement.

In tracing how Wyatt's poems emerge out of his life and times, Brigden brings to bear a vast range of literary and historical primary sources. Among the most intriguing sections of the book are those that set Wyatt in the context of his diplomatic career: Brigden has mined several European archives to bring us the fullest picture yet of his activities in war-torn Italy and imperial Spain, revealing a man who took exceptional risks on his own part and those of his king. Captured by Spanish troops outside Bologna in early 1527, he escaped weeks later by the skin of his teeth. Almost a decade on, at the court of Charles V, Wyatt's daring eloquence allowed him to tread very close to the wind indeed. At a time when the Inquisition more or less regarded all Englishmen as heretics, and submitted a number of them to the auto-da-fé – one Lutheran, John Tack, reportedly jumped into the flames as though into a bed of roses – Wyatt and his household were under intense scrutiny. The papal nuncio, the Inquisition and the Pope himself referred to Wyatt as "a demon".

Brigden's impulse to leave no archival or interpretative stone unturned can tend to result in passages that are saturated in detail and associative wordplay, yet her valuable book shows Wyatt as a master at work: a man who, in saying so much while revealing nothing, gave fullest expression to the tumultuous, paranoid world of the 1530s. Occasionally, though, this most poised of poets did let his mask slip. On 28 July 1540, as Thomas Cromwell prepared to face the executioner, he turned to bid farewell to Wyatt and to ask for his prayers. Wyatt, reportedly, was crying so hard that he "could not answer him for tears". For once, he was lost for words.

• Thomas Penn's The Winter King is published by Penguin.

• This article was amended on 17 December 2012 to correct the spelling of Susan Brigden's surname in the headline

Sign up for the Guardian Today

Our editors' picks for the day's top news and commentary delivered to your inbox each morning.